4 ms·
Recharging it isn't that simple We use zeolite as a water scavenger in high vacuum systems, it's tremendously good at grabbing onto water BUT because it's so
by excuse-me 14y ago
Recharging it isn't that simple
We use zeolite as a water scavenger in high vacuum systems, it's tremendously good at grabbing onto water BUT because it's so porous and very low thermal conductivity it's a real pain to heat it enough to get all the water out again.
We have a heater resistor at the bottom of a small can of this and the top of the pellets a few cm away is cool enough to touch.
You might do better with a microwave system but then the inefficiencies are going to hurt.
Why not use one of the many phase change salt solutions that are also used for rechargeable heater packs?
- Zaak 14y agoI wonder if you could incorporate a wire mesh into the zeolite to improve the heat distribution.
- olefoo 14y agoIf you could figure out a good way to integrate the heating element and the the zeolite on a surface like a menger sponge you would have a very high surface area and good thermal response characteristics.
- gte910h 14y agoA drum dryer like you use for clothing sounds built to take water out of these things (with grates smaller than the pellets of course).
- DanBC2 14y agoNoisy as hell though. Also, how robust are the pellets? Tumbling them may create a lot of dust. Damp dust would be tricky to control. I used to have to dry silica gel bags. We'd put them in a temperature controlled oven for a few hours, it'd ramp the heat up and fans would pull air through. That worked quite well, but was only for small quantities. I guess you could have many mesh racks with heating at the base (or even through the mesh) and fans at the top to extract moist air. Drying that air and re-using it would handy.
- excuse-me 14y agoThe stuff is fragile (or at least the 5nm molecular sieve type)- if you shake it too much you make dust which blocks the pores
- rcthompson 14y agoIs it such a major problem that it leads to major efficiency losses (measured as joules of output energy over joules of input energy required to "recharge")?
- nwmcsween 14y ago> ..microwave system but then the inefficiencies are going to hurt. What inefficiencies? A microwave should be more efficient due to it only energizing H2O bonds.
- rcthompson 14y agoSurely a microwave oven is not 100% efficient in converting the input electrical energy into output heat in the object to be heated? I'm not sure how near 100% it is.
- AnthonBerg 14y agoHey good question. Kitchen microwaves: ~64% – http://en.wikipedia.org/wiki/Microwave_oven#Heating_efficiency http://en.wikipedia.org/wiki/Microwave_oven#Heating_efficien...
- debacle 14y agoThat's actually pretty good.